1. Technical Field
The present invention relates generally to an improved data processing system, and in particular to a method and apparatus for processing graphics data. Still more particularly, the present invention provides a method and apparatus for caching or storing graphics data in a manner to reduce bandwidth usage of a system bus.
2. Description of Related Art
Data processing systems, such as personal computers and work stations, are commonly utilized to run computer-aided design (CAD) applications, computer-aided manufacturing (CAM) applications, and computer-aided software engineering (CASE) tools. Engineers, scientists, technicians, and others employ these applications daily. These type of applications are normally graphics intensive in terms of the information relayed to the user. On these types of data processing systems, the graphics applications require priority access to system resources.
On the server side, however, the demand for fast graphics processing is less than that on the client side data processing systems. Instead, on a server data processing system, the emphasis is on the speed at which requests can be handled and processed. For example, a server may receive thousands of requests in an hour for web pages being hosted on the server. On server class data processing systems, a graphics display is used for system management and other low priority activities. The rendering used for these activities often requires the use of large patterned areas, such as, for example, window backgrounds and patterned buttons. Repeatedly sending a pattern from a memory or other storage across a bus to a graphics adapter for display uses a large portion of the system bus bandwidth. This usage reduces the availability of bus resources for higher priority applications, such as those used for responding to client requests.
Therefore, it would be advantageous to have an improved method and apparatus for handling graphics data in a manner in which the number of bus accesses are reduced.
The present invention provides a method and apparatus in a data processing system for processing a request to display a pattern. A plurality of partitions is created in a memory in a graphics adapter in the data processing system, wherein each partition within the plurality of partitions has a size equal to each of the other partitions within the plurality partitions. A determination is made as to whether the pattern is present within the plurality of partitions. The pattern is displayed using the plurality of partitions if the pattern is present within the plurality of partitions. The pattern is retrieved from another location if the pattern is absent from the plurality of partitions. Responsive to retrieving the pattern from another location, the pattern is stored if the pattern is within the size.